Adjustable dumbbell

ABSTRACT

An adjustable dumbbell comprising a bar assembly which can retain a user-selectable number of weight elements, user-selectable by actuation of sliding locking tabs. A base for supporting the bar assembly and weights while not in use is also disclosed. The bar assembly may possess notches into which the tabs of the weight plates may fit to retain weight plates in the lengthwise direction, and user-slideable tabs integral to the bar assembly which restrain selected plates to the notches by passing through the small notch and preventing transverse relative movement. With weight elements seated in the stand, and the bar assembly seated in an arrangement of weight plates, a user can select the number of weight plates connected to the bar assembly by extending or retracting the sliding lock tabs, and then lift the dumbbell from the stand carrying the desired number of plates, leaving the remaining plates in the stand.

TECHNICAL FIELD OF THE INVENTION

This invention is in the field of personal exercise equipment and more specifically relates to an adjustable dumbbell system which allows for the configuration of a dumbbell for use with a user selectable number of weight elements.

BACKGROUND OF THE INVENTION

Dumbbells are ubiquitous devices used for weight-training exercises. The strength of dumbbell users varies, and for a given user, the most effective amount of weight for an exercise varies from exercise to exercise, or from one point in time to another. As such, users typically desire a plurality of conventional fixed-weight dumbbells, or a dumbbell system which enables removal and replacement of a variety of weights. In a home or a small gym, it may be inconvenient or impractical to store a plurality of dumbbells, and it is inconvenient and time-consuming to remove and replace weights in dumbbells that enable it.

In response to these issues, adjustable dumbbells have been developed which allow users to rapidly change the weight. In many adjustable dumbbell systems, a change to the weight of the dumbbell is performed by placing the dumbbell in a dedicated base and manipulating a selector, which connects or disconnects weight elements from the dumbbell as necessary to achieve the desired weight. Many of these adjustable dumbbells are bulkier than their traditional counterparts due to their complex or delicate mechanisms, do not allow small increments of weight adjustment, or compromise on ergonomics.

BRIEF SUMMARY OF THE INVENTION

The present invention, an adjustable dumbbell system, may comprise a dumbbell with a bar assembly and weight elements (plates) that may be selectably connected to the bar assembly, and a stand which may support the dumbbell or any idle weight elements in a ready position. The weight elements may be defined by only a thickness and a profile shape and may have no gaps between them when either mounted to the bar assembly or supported idle on the stand.

The bar assembly may comprise a hand-grip and a mechanism to selectably connect weight elements to the bar assembly.

Actuation of the selection mechanism may be enacted by rotating the hand-grip about the bar assembly's long axis to actuate sliding lock tabs which may selectably engage notches in individual weight elements, allowing the user to increase or decrease the quantity of weight elements locked to the bar assembly. The bar assembly may have a pattern of notches which may engage features of the weight elements to lock weight elements to the bar assembly in the direction of the long axis of the bar assembly.

In preferred embodiments, weight elements may be profile-cut steel plate, the bar assembly may be four pieces of profile-cut steel plate bolted or welded together and may have a molded-plastic hand-grip and a plastic gap-filler between the hand-grip and the steel components of the bar assembly, and the stand may be profile-cut and bent steel plate.

In one embodiment of the present invention there is provided an adjustable dumbbell system comprising a bar assembly having a rotatable actuator rotatable about a long axis of the bar assembly; extendable engagement members disposed at opposite ends of the bar assembly and extendable along the long axis of the bar assembly, the extendable engagement members provided with external threading; the rotatable actuator provided with internal threading configured for meshing with the external threading of the extendable engagement members such that rotation of the rotatable actuator in a first direction imparts a first linear directional movement to distally extend the extendable engagement members, and rotation of the rotatable actuator in a second direction imparts a second and opposite linear directional movement to retract the extendable engagement members.

In addition to the bar assembly, the device comprises two spaced-apart sets of weight members, each of the weight members comprising an aperture configured for receipt of one of the extendable engagement members.

In operation of the adjustable weightlifting system, when the rotatable actuator is rotated in the first direction the extendable engagement members distally extend and pass through the aperture of one or more of the weight members in series thus engaging one or more of the weight members. Conversely when the rotatable actuator is rotated in the second direction, the extendable engagement members retract back out of the aperture of the one or more of the weight members in series to disengage from the one or more of the weight members.

In some embodiments, the rotatable actuator comprises a cylindrical hand grip disposed around a central portion of the bar assembly and rotatable about the long axis of the bar assembly.

In some embodiments the bar assembly comprises notched ends disposed at opposite ends of the bar assembly, the notched ends provided with laterally-disposed guideways, each extendable engagement member slidably disposed in one of the guideways. Where this is the case, the aperture may comprise a vertical notch from an upper edge of the weight member to a centre of the weight member, the vertical notch configured for receipt of one of the notched ends of the bar assembly, the vertical notch comprising a tab at a bottom of the vertical notch such that when the notched end is received in the vertical notch a notch of the notched end engages the tab to restrain distal movement of the weight member relative to the bar assembly.

In some preferable embodiments the aperture further comprises a horizontal notch positioned at the bottom of the vertical notch, the horizontal notch configured for receipt of the extendable engagement member, wherein when the notched end is received in the vertical notch and the hand grip is rotated in the first direction, the extendable engagement members move in the first linear direction passing through the horizontal notch of one or more of the weight members in series, such that lifting of the bar assembly will cause the extendable engagement members to press up against the horizontal notch and lift the one or more weight members, and wherein when the notched end is received in the vertical notch and the hand grip is rotated in the second direction, the extendable engagement members move in the second and opposite linear direction passing back out of the horizontal notch of one or more of the weight members in series to disengage from the one or more weight members.

Some embodiments of the invention also include a stand for receipt and support of the sets of weight members, the stand comprising notches for receiving the weight members and supporting the weight members in an orientation allowing the extendable engagement members to pass through the apertures. The weight members may be supported in a general vertical orientation, or may be supported in an orientation angled off of vertical.

In further embodiments of the invention the bar assembly further comprises a protuberance configured to engage the aperture and prevent rotation of the weight members relative to the extendable engagement members when the extendable engagement members are disposed in the apertures.

Some embodiments of the invention and system of the present invention further comprise corresponding holes in the rotatable actuator and the extendable engagement members and a pin configured for receipt in the holes, such that receipt of the pin in the holes prevents further rotation of the rotatable actuator relative to the extendable engagement members thereby securing the engagement of the extendable engagement members with the one or more of the weight members.

The adjustable weightlifting system of the present invention permits the selective loading of a dumbbell for use by a weightlifting user. As outlined above and throughout, the adjustable weightlifting system comprises two spaced apart sets of weight members placed to permit placement of an extendable bar assembly therebetween, each of the weight members including an opening configured to receive and engage an extendable engagement member of a bar assembly; and an extendable bar assembly comprising an elongate bar having a long axis and two extendable engagement members contained within and extendable from opposite distal ends of the bar along the long axis. Upon positioning the extendable bar assembly in a contracted position with the extendable engagement members retracted within the elongate bar, when the engagement members are extended from the distal ends of the bar assembly they can each extend through and engage the opening of one or more of the weight members in series resulting in a selectively weighted dumbbell for use. Upon retraction of the extendable engagement members into the elongate bar, when serially engaging one or more of the weight members, the extendable bar assembly will disengage from set weight members.

As outlined, the elongate bar could further comprise a rotatable actuator rotatable about the long axis which also includes internal threading capable of engaging external threading on the external engagement members. Upon rotation of the rotatable actuator in a first direction imparts a first linear directional movement to distally extend the extendable engagement members from the distal ends of the elongate bar, and rotation of the rotatable actuator in a second direction imparts a second and opposite linear directional movement to retract the extendable engagement members—when the rotatable actuator is rotated in the first direction, the extendable engagement members distally extend and pass through the opening of one or more of the weight members in series, thus engaging the one or more of the weight members; and when the rotatable actuator is rotated in the second direction, the extendable engagement members retract back out of the opening of the one or more of the weight members in series to disengage from the one or more of the weight members.

As outlined above certain embodiments of the present invention would include a bar assembly that comprises notched ends disposed at opposite ends of the bar assembly and provided with guideways, each extendable engagement member slidably disposed in one of the guideways. It will be understood that other approaches will also be understood by those skilled in the art and all are contemplated within the scope hereof.

In embodiments of the bar assembly that comprise notched ends at the opposing ends of the bar assembly with guideways, the corresponding openings in each weight member might comprise a vertical notch from an upper edge of the weight member to a centre of the weight member configured for receipt of one of the notched ends of the bar assembly; and a tab at a bottom thereof such that when the notched end of the bar assembly is received in the vertical notch, a corresponding notch of the notched end of said bar assembly engages the tab to restrain distal movement of the weight member relative to the bar assembly.

In some embodiments the opening of each weight member might also comprise a horizontal notch configured for receipt of the extendable engagement member, positioned at the bottom of the vertical notch—when a notched end of the bar assembly is received in the vertical notch and the hand grip is rotated in the first direction, the extendable engagement members move in the first linear direction passing through the horizontal notch of the one or more of the weight members in series, such that lifting of the bar assembly will cause the extendable engagement members to press up against the horizontal notch and lift the one or more weight members. In such embodiments, when the notched end of the bar assembly is received in the vertical notch and the hand grip is rotated in the second direction, the extendable engagement members move in the second and opposite linear direction passing back out of the horizontal notch of the one or more of the weight members in series to disengage from the one or more weight members.

The invention can also comprise a stand for the resting storage and positioning of the weight members, which will result in the resting support of the two spaced-apart sets of weight members in resting positions for engagement by the extension of the bar assembly, said stand comprising slots for receiving the weight members and supporting the weight members in an orientation allowing the extendable engagement members to pass through the openings.

Certain embodiments of the bar assembly of the present invention will also comprise a surface configured to engage an innermost of the weight members to prevent movement of the weight members along the long axis once engaged.

Certain embodiments of the dumbbell system of the present invention include a weight setting indicator system as a component of the rotatable actuator. The weight setting indicator system consists of a plurality of apertures extending through and disposed around the actuator through which the user can see at least a portion of at least one of the extendable engagement members through each aperture. The second component of the weight setting indicator system are selectively aligned weight indicia which indicate the total weight of the dumbbell system based upon the number of blade elements engaged by the extended engagement members. Either the individual apertures, or the engagement members themselves inside of the rotatable actuator, could include total weight setting indications which would indicate the weight of the dumbbell system based upon the alignment of a particular weight indicia with a particular aperture through the actuator. The user could selectively adjust the weight of the dumbbell while the dumbbell was in its resting position, by rotating the actuator until the selected aperture was aligned with the selected weight indicia indicating based upon the known weight of individual weight elements and the extended length of the engagement members what the total weight of the dumbbell is at the selected extension of the engagement members.

In certain embodiments of the weight setting indicator system, the weight indicia with the weight values or markings on the engagement members which become visible through an active aperture a corresponding selected weight of the dumbbell.

In certain embodiments of the weight setting indicator system, the weight indicia themselves would be the interior end of at least one of the engagement members which the user could see through the apertures and use as an alignment indicator with the apertures as labelled to select a desired weight of the dumbbell.

The user could use the weight setting indication system in these embodiments to selectively adjust the operating weight of the dumbbell by extending or retracting the engagement members until the appropriate weight indicia were aligned with appropriate aperture indicating the desired operating weight of the dumbbell. As the engagement members were retracted resulting in a decrease in the number of weight elements engaged and unattended decrease in the operating weight of the dumbbell, the weight indicia would align with apertures indicating a lower corresponding weight value.

In operation of the system of the present invention, the user can position the retracted bar assembly between the two spaced apart sets of weight members and extend the extendable engagement members to engage the desired number of weight members. Following the completion of weightlifting with the attached selected amount of weight, the bar assembly can be contracted again to remove the weights therefrom.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an example of the disclosure and, together with the foregoing general description and the following detailed description, delineate the principles of these examples:

FIG. 1 is an isometric view of an adjustable dumbbell system in accordance with an example of the present disclosure;

FIG. 2 is a proximal isometric view of the bar assembly of FIG. 1 ;

FIG. 3 is an isometric view of the weight element of FIG. 1 ;

FIG. 4 is an isometric view of the handle of FIG. 2 ;

FIG. 5 is a cross-sectional view of the handle of FIG. 2 taken along line 5-5 of FIG. 4 ;

FIG. 6 is an isometric view of a sliding lock tab of FIG. 2 ;

FIG. 7 is a top plan view of the bar assembly of FIG. 2 with the sliding lock tabs half extended;

FIG. 8 is a side view of the bar assembly of FIG. 2 with the sliding lock tabs half extended;

FIG. 9 is a cross-sectional view of the bar assembly of FIG. 2 taken along line 9-9 of FIG. 8 with the sliding lock tabs half extended;

FIG. 10 is an isometric view of the adjustable dumbbell system of FIG. 1 showing the dumbbell raised from the stand, dumbbell having approximately two-thirds of the weight elements connected to the bar assembly;

FIG. 11 is an end view of the adjustable dumbbell system as portrayed in FIG. 10 ;

FIG. 12 is a cross-sectional view of the adjustable dumbbell system as portrayed in FIG. 10 taken along line 12-12 of FIG. 11 ;

FIG. 13 is a cross-sectional view of the adjustable dumbbell system as portrayed in FIG. 10 taken along line 13-13 of FIG. 11 ;

FIG. 14 is a cross-sectional view of the adjustable dumbbell system as portrayed in FIG. 10 taken along line 14-14 of FIG. 11 ;

FIG. 15 is an end view of an alternate embodiment of a weight element in accordance with the present invention;

FIG. 16 is a perspective view of a system in accordance with the present invention using the weight elements of FIG. 15 ;

FIG. 17 is a perspective view of one embodiment of an adjustable weight system in accordance with the present invention including a weight setting indicator system;

FIG. 18 is a cutaway view of the article of FIG. 17 demonstrating the interior components of the system involved in the weight setting indicator;

FIG. 19 is a side view of the rotatable actuator of FIG. 17 ; and

FIG. 20 is a perspective view of an extension element;

FIG. 21 is a side view of a rotatable actuator in accordance with FIG. 17 demonstrating a larger plurality of viewing apertures disposed around the actuator for the purpose of weight setting indication.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Throughout the following description, specific details are set forth in order to provide a more thorough understanding to persons skilled in the art. However, some well-known elements are not shown or described in detail to avoid unnecessarily obscuring the disclosure. The following description of the invention is not intended to be exhaustive or to limit the invention to the precise form of any exemplary embodiment. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense.

The present invention is directed to an adjustable dumbbell system for weight training exercises.

Referring to FIG. 1 , an adjustable dumbbell system 100 is illustrated, which may comprise a dumbbell 101, a bar assembly 102, two stacks 103 of weight elements 104, and a stand 105 to hold the dumbbell 101 while it is not in use, or any un-selected weight elements 104 while the dumbbell 101 is in use. The weight elements 104 comprising each stack 103 may not have gaps between them except where the dumbbell 101 is separated from weight elements left idle on the stand 105.

Referring to FIGS. 2 and 3 , the bar assembly 102 may have two ends 106, onto which a selectable quantity of weight elements 104 may be locked, which may start with the innermost weight elements 104, progressively adding to the stacks 103 outward as the selected weight quantity is increased. Weight elements 104 may be restrained from moving distally along the long axis of the bar assembly 102 by pluralities of notches 108 at each end 106, arranged so that the tab 113 on each weight element 104 has a notch 108 to be restrained by, said tabs 113 may be laterally alternated from one weight element 104 to the next in the stack 103. Weight elements 104 may be restrained from rotating or moving proximally along the long axis of the bar assembly 102 by flat surfaces 111 on the bar assembly which contact the innermost weight element 104; any portion of the stack 103 of weight elements 104 that may be locked to the bar assembly 102 may also benefit from this restraint as there may not be gaps between weight elements 104. The weight elements 104 may be selectably locked to the bar assembly 102 with the bottom 115 of the big notch 114 being held up to the bottom side of the bar assembly 102 by virtue of sliding lock tabs 109 which may be positionable along the long axis of the bar assembly 102 and otherwise restrained to the bar assembly 102 by the guideway 110, and may bear against small notches 116 when the are extended to pass through said notches, serving to restrain weight elements 104 such that the notches 108 remain engaged to the tabs 113. The position of the sliding lock tabs 109 along the guideway 110 may dictate the quantity of weight elements 104 locked to the bar assembly 102.

Referring to FIGS. 4, 5, and 6 , the hand grip 107, which may be rotatably connected to the bar assembly 102, may have internal threads 118 at each end, which may be of opposite hand on each end, which may engage partial external threads 120 on the lock tabs 109. Referring to FIG. 7 , rotation of the hand grip 107 by the user may impart linear motion to the lock tabs 109 by virtue of the internal threads 118 of the handle meshing with the partial external threads 120 on the lock tabs 109. Referring to FIG. 8 , the hand grip 107 may be equipped with a device to restrain rotation while the dumbbell is in use to prevent the tabs 109 from being retracted, which may ensure weight elements 104 are prevented from falling off; said device may be a removable pin inserted through hole 112 which may pass through the hand grip 107 and the bar assembly 102.

Referring again to FIG. 1 , at rest, the weight elements 104 may be arranged in the stand 105 with the bar assembly 102 placed down in the slot in the stacks 103 formed collectively by the big notches 114 in the weight elements 104.

Referring to FIGS. 10 and 11 , when the bar assembly 102 is lifted from the stand 105, a quantity of weight elements 104 are pulled out with the bar assembly 102, said quantity may be dependent upon the position of the lock tabs 109 as set by the user; any remaining weight elements 104 may be held in a ready position in the stand 105 by virtue of notches 121 in the stand 105 matching the notches 117 of the weight elements 104 in the remaining stack, in a manner similar to that of the notches 108 in the bar assembly 102 matching the tabs 113 in the weight elements 104.

Referring to FIGS. 12, 13, and 14 , the adjustable dumbbell system 100 as arranged as in FIGS. 10 and 11 is shown in several cross-sectional views in order to describe the system for selectably locking the weight elements 104 to the bar assembly 102 with further clarity.

Referring to FIG. 12 , the sliding lock tab 109 on one end 106 of the bar assembly 102 which may be confined by the guideway 116 is shown deployed in a position such that it passes through the small notches 116 of several weight elements 104, ensuring the bottoms 115 of the large notches 114 remain engaged with the notches 108 of the bar assembly 102.

Referring to FIG. 13 , the notches 108 on the near side of the bar assembly 102 as cut by section line 13-13 in FIG. 11 may restrain the tabs 113 on every second weight element 104 in the direction of the bar assembly's 102 long axis; and referring to FIG. 14 , the notches 108 on the far side of the bar assembly 102 as cut by section line 14-14 in FIG. 11 may restrain the tabs 113 on the remaining weight elements 104 in the direction of the bar assembly's 102 long axis.

In other embodiments of the invention, the notches 108 may be identical from one to the next, and the large notch 114 and bottom of the large notch 115 in each weight element 114 may be shaped to engage the bar assembly's 102 notches 108. In still other embodiments, notches 108 may be substituted with tabs or some other protrusion and may require a gap between weight elements or additional processing to accommodate said tabs or protrusions. In still other embodiments, the arrangements of notches 108 may be on opposite faces of the bar assembly 102 rather than on the ‘bottom’ of it.

Referring to FIGS. 15 and 16 , and adjustable barbell system in accordance with the present invention is shown using an alternate configuration of the weight elements 104 and the notched ends 108. Specifically, an asymmetrical feature 123 at the bottom 115 of the notch 114 may be used instead of a tab 113; the bar assembly 102 having corresponding notched ends 108 to axially restrain the weight elements 104.

It will be apparent to those of skill in the art that by routine modification the present invention can be optimized for use in a wide range of conditions and application. It will also be obvious to those of skill in the art that there are various ways and designs with which to produce the apparatus and methods of the present invention. The illustrated embodiments are therefore not intended to limit the scope of the invention, but to provide examples of the apparatus and method to enable those of skill in the art to appreciate the inventive concept.

In addition to the general concept of an adjustable weightlifting system as outlined, the invention also includes a novel weight setting indicator system which can be used by the user to adjust and visibly ascertain the selected operating weight of the dumbbell system. Referring first to FIGS. 17, 18, and 19 there is shown one embodiment of an adjustable dumbbell system in accordance with the present invention including a novel weight setting indicator system. Dumbbell 101 is shown, along with the distal ends 124 of the extendable engagement members 109. The rotatable actuator 107 comprising a handgrip is also shown.

Shown on the actuator 107 are a plurality of apertures 131 with corresponding weight labels 130 indicating the selected weight of the dumbbell. Alignable weight indicia 132 can be seen through the apertures 131 such that upon the alignment of the weight indicia 132, being an interior end of an engagement member, with a particular selected aperture 131 with the particular weight indication 130, the user can know the selected weight of the dumbbell. The weight labels 130 will be applied and positioned on the actuator 107 based upon the known weight of the individual weight elements—for example, where the extendable engagement members will engage seven weight plates at each end of the dumbbell, if each weight plate weighs 5 pounds, the total of 14 weight plates would weigh 70 pounds and the aperture could be positioned and labelled accordingly based upon wherever the necessary interior and the engagement member comprising the weight indicia 132 in such an embodiment would be located. The interior end 132 can be seen as a portion of the extendable engagement member 109, and the selected engaged number of weight elements 104 can also be seen.

FIGS. 20 and 21 demonstrate views of the rotatable actuator 107 of FIG. 17 , demonstrating different positioning of apertures 131 with weight labels 130 applied thereto. It will be understood that variations and modifications of the weight setting indication system will be understood to those skilled in the art and all such modifications are contemplated within the scope of the present invention. These variations for example may include the machining or application of numerical weight indications on the threaded surface of the extendable engagement members which would become visible through a viewing aperture, as a modification or alternate configuration instead of that shown in FIG. 17 .

Using the weight setting indication system of the embodiment of FIG. 17 , the user can see the selected weight of the dumbbell system 101 by adjusting the weight indicia 132 and the apertures 131 by extending or retracting the engagement members 109 until the desired weight indicia 132 are aligned with an active aperture indicating the current use weight 132 of the system.

Those skilled in the art will recognize that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the scope of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. The terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps not expressly referenced. 

1. An adjustable dumbbell system comprising: a. two spaced-apart sets of weight members placed to permit placement of an extendable bar assembly therebetween, each of the weight members including an opening configured to receive and engage an extendable engagement member of a bar assembly; and b. an extendable bar assembly comprising an elongate bar having a long axis and two extendable engagement members contained within and extendable from opposite distal ends of the bar along the long axis whereby: i. upon positioning the extendable bar assembly in a contracted position with the extendable engagement members retracted within the elongate bar, when the engagement members are extended from the distal ends of the bar assembly they can each extend through and engage the opening of one or more of the weight members in series resulting in a selectively weighted dumbbell for use; and ii. upon retraction of the extendable engagement members into the elongate bar, when serially engaging one or more of the weight members, the extendable bar assembly will disengage from set weight members.
 2. The system of claim 1 wherein: a. the elongate bar further comprises a rotatable actuator rotatable about the long axis and comprises internal threading; b. the extendable engagement members are provided with external threading configured to mesh with the internal threading of the rotatable actuator; whereupon rotation of the rotatable actuator in a first direction imparts a first linear directional movement to distally extend the extendable engagement members from the distal ends of the elongate bar, and rotation of the rotatable actuator in a second direction imparts a second and opposite linear directional movement to retract the extendable engagement members; wherein when the rotatable actuator is rotated in the first direction, the extendable engagement members distally extend and pass through the opening of one or more of the weight members in series, thus engaging the one or more of the weight members; and wherein when the rotatable actuator is rotated in the second direction, the extendable engagement members retract back out of the opening of the one or more of the weight members in series to disengage from the one or more of the weight members.
 3. The system of claim 2 wherein the rotatable actuator comprises a cylindrical hand grip disposed around a central portion of the bar assembly and rotatable about the long axis of the bar assembly.
 4. The system of claim 3 wherein the bar assembly comprises notched ends disposed at opposite ends of the bar assembly and provided with guideways, each extendable engagement member slidably disposed in one of the guideways.
 5. The system of claim 4 wherein the opening in each weight member comprises: a. a vertical notch from an upper edge of the weight member to a centre of the weight member configured for receipt of one of the notched ends of the bar assembly; and b. a tab at a bottom thereof such that when the notched end of the bar assembly is received in the vertical notch, a corresponding notch of the notched end of said bar assembly engages the tab to restrain distal movement of the weight member relative to the bar assembly.
 6. The system of claim 5 wherein the opening of each weight member further comprises a horizontal notch configured for receipt of the extendable engagement member, positioned at the bottom of the vertical notch; wherein when a notched end of the bar assembly is received in the vertical notch and the hand grip is rotated in the first direction, the extendable engagement members move in the first linear direction passing through the horizontal notch of the one or more of the weight members in series, such that lifting of the bar assembly will cause the extendable engagement members to press up against the horizontal notch and lift the one or more weight members; and wherein when the notched end of the bar assembly is received in the vertical notch and the hand grip is rotated in the second direction, the extendable engagement members move in the second and opposite linear direction passing back out of the horizontal notch of the one or more of the weight members in series to disengage from the one or more weight members.
 7. The system of claim 1 further comprising a stand for supporting the two spaced-apart sets of weight members in resting positions for engagement by the extension of the bar assembly, said stand comprising slots for receiving the weight members and supporting the weight members in an orientation allowing the extendable engagement members to pass through the openings.
 8. The system of claim 7 wherein the weight members are supported in a generally vertical orientation.
 9. The system of claim 7 wherein the weight members are supported in an orientation angled off of vertical.
 10. The system of claim 1 wherein the bar assembly further comprises a surface configured to engage an innermost of the weight members to prevent movement of the weight members along the long axis once engaged.
 11. The system of claim 2 further comprising a pin configured to prevent further rotation of the rotatable actuator relative to the extendable engagement members thereby securing the engagement of the extendable engagement members with the one or more of the weight members.
 12. The system of claim 3 wherein the rotatable actuator further comprises a weight setting indicator system namely: a. a plurality of apertures through and disposed around the actuator, allowing the user to see at least a portion of at least one of the extendable engagement members through each aperture; and b. selectively aligned weight indicia which indicate the total weight of the system based on the number of weight elements engaged by the extended engagement members; wherein the user can see the selected weight of the dumbbell system by adjusting the weight indicia and the apertures by extending or retracting the engagement members until the desired weight indicia are aligned with an active aperture indicating the current use weight of the system.
 13. The system of claim 12 wherein the weight indicia are weight values or markings on the engagement members which become visible through an active aperture.
 14. The system of claim 12 wherein the weight indicia are the interior ends of the engagement members, whereby the user will see the interior ends of the engagement members through the apertures each of which is marked with a weight value. 